Mechanism for operating car-brakes.



PATENTED MAR. 15, 1904. J. L. PEAGOGK. MEGHANISM FOR OPERATING GAR BRAKES.

APPLICATION FILED SEPT. 3, 1903.

2 SHEETS--SHEET l.

N0 MODEL.

110.754,603. PATENTED MAR.15,1904.

i J. L. PEAcooK.

MECHANISM FOR OPERATING GARBRAKBS. ArPLvIoATIoN FILED SEPT. a, 190s.

N0 MGDBL. 2 SHEETS-SHEET 2.

mummy;

UNTTEDo- STATES Patented Meren 15, 1904.

JOHN LANGFORD PEACOCK, OF BUFFALO, NEW YORK.

MECHANISM FOR OPERATIONS CAR-BRAKES.

SPECIFICATION forming part ef LettereratentfNe. 754,603, dated March 1,5, 1904.

' Application led September 8, 1903K Serial No. 171,837. (No model.)

To all when@ it may concern:

Be it known that I, JOHN LANGEoRD PEA- CooK, of the city of Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Mechanism for Operating Oar-Brakes; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings,

.l0 whichform part of this specification.

VThe present invention relates to an improved brake-operating mechanism general in its application, and particularly a valuable adjunct to the present hand-brake of electrically-pro-` pelled or trolley cars.

The characteristic feature of the present invention is to embodyl in a compensating device a spiral form of chain orcable drum operatively connected with the primal operating 2O medium, and has for its object to take up rapidly the slack of the brake mechanism of the car with a minimum angular movement of the brake-handle, to utilize with advantage the saving thus made, to more effectually apply with a gradually-increasing force the brakeshoe ,to the wheels by a relatively proportionate increase of the angular movement of the brake-handle, and to maintain a maximum braking force for any desirable degree of the major portion of the said angular movement of the brake-handle. By this means the augmented braking force is sufiicient to cause cessation of movement in a comparatively short distance with a minimum expenditure of manual energy and without incurring theobjectionable feature of additional turns of the brake-handle over andabove that found practical for rapid braking of cars. Appliances have been devised with a similar object in view to make more perfect the hand-brake vantage derived from the eccentric or analo- It must be borne in-mind that.

gous device. perfection 1n a brake devlcepermits of a variation in the lengthrof chain wound upon the drum in operating the brake,while maintaining a uniform braking force. Owing to the constant wearingaway of the brake-shoes and the intermittent variation of the mechanism due to climatic changes, the length of chain wound upon the drum is a variable quantity, and the maximum braking force cannot be maintained without recourse to an auxiliary adjustment, which is is not a desideratum.

The invention consists in part of the application of roller-bearings, particularly in the instance of the chain or cable drum, and certain details of construction, as hereinafter more fully described, reference being had to the accompanying draw-ings, forming part thereof, in which similar figures of reference refer to like parts throughout;

Figure l is a top plan view ofthe improved brake-operating mechanism with a portion of the casing removed tomore clearly show the operating elements. Fig. 2 is a side elevation of Fig. 1 with the detachable portions of the casing entirely removed. Fig. 3 is a crosssectional view on the line A to A of Fig. 1. FigA is a view in detail of the roller-bearing. Fig. 5 is a cross-sectional view on the line B to B of Fig. 4. Fig.'6 is a detail View of the roller-bearing, showing the cage with the rolls removed; and Fig. 7 is an inverted plan view of the spiral drum, showing the contour of the same and the integral gear forming part thereof.

The actuating elements of the brake-operating device are carried in a substantial frame and inclosed, in as far as is practical, by a casing,- a portion of which is detachable, as shown. The frame l is of the skeleton type and preferably cast in one piece and provided with lateral lugs 2, Vthree of which are found most desirable.V Theadvantages derived from supporting the devicev at three points is obvious, insuring at all times a true and rigid support without producing any undue strain in the frame of the device when bolted or otherwise secured to' the under side, of the platform. The present brake post or spindle and its appurtenances can be employed with but few changes and .serve as the actuating medium for the brake-operating device.

The lower extremity of the brake-post 3 passes downwardly through the upper and lower portions of the frame 1 and is journaled therein and serves as the spindle for the pinion 4, carried fast thereon by a key or feather, preferably the latter, allowing the brake-post to be readily withdrawn or inserted.

In alinement with and parallel of the aforesaid spindlc 3 is a vertically-disposed stud 5, terminally fixed in the upper and lower portions of the frame 1 and secured in a manner to insure against its displacement, for which purpose the enlarged head of lsaid stud is on the upper side of said frame, as shown.

Carried upon the stud 5 and adapted to revolve freelythereon is a spur-gear 6, in mesh with the aforesaid pinion 4 and integral with the brake-chain drum 7, also carried thereon. rlhe ratio of the spur-gear 6 and pinion 4 is relatively proportionate to the length of chain wound upon the dru1n7 in operating the brake.

By referring to Fig. 7 it will be seen that, broadly speaking, the drum 7 has a spira'. periphery, upon which the brake chain 8 is wound; but owing to the prevailing conditions regulating the operation of a device of this nature it is essential for to obtain the highest ciiciency to modify the spiral form of drum in such a manner that the contour of the major'portion 9 resembles aparabola merging in the minor or cylindrical portion 10. Commencing at the greatest radius of the drum, at which point the chain or cable is made fast, the slack of the brake-chain is rapidly taken up by the major portion of the drum gradually diminishing with an increasing purchase, the maximum being attained when the cylindrical portion of the drum is reached. rlhe minor or cylindrical portion of the drum remains to take up any additional chain without further increasing the turning moment per unit length of chain, in part the advantages alluded to in the preamble of this specification;

rlhe manner of attaching thebrake-chain to the drum is simple and efficient, permitting readily the attaching and detaching of thc chain. At the greatest radius of the drum is formed in the periphery a pocket or recess 11 to receive the terminal link of the brake-chain 8, through which passes the bolt 12, as shown.

By the adaptation of roller-bearings, particularly in the instance of the brake-chain drum, the portion of the device subjected to a forceful strain, the friction is reduced to a minimum. Any well-known form of roller-bearing that will fulfil the requirements in this instance can be employed. Illustrated by Figs. 4, 5, and 6 is a simple and eficent rollerbearing comprising a series of cylindrical rolls 13, retained by a cage 14, consisting of two annular collars supported apart by studs, as shown, and provided with recesses for the reception of the rolls.

Although advantageous, the adaptation of roller-bearings is not an indispensable feature of this invention. Anyother form of bearing may be substitutedcwithout departing from the spirit of the invention.

Having described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a brake-actuating device, the combination with the brake-post, of apinion on the lower end of said post, a gear in mesh with said pinion and integral with a spiral brakechain drum adapted to operate with a variable leverage, said spiral tapering downward to a cylindrical part and being in its broadest portion of parabolic curve, substantially as set forth.

2. In a brake-actuating device, the combination of roller-bearings with the brake-post, a pinion on the lower end of said post, abrakeactuating drum comprising an integral spiral and concentric periphery, a gear in mesh with said pinion and operating said drum, and a brake-chain attached to said drum and adapted to operate with a variable leverage, substantially as and for the purpose set forth.

3. In a brake-actuating device, the combination of roller-bearings with the brake-actu ating drum and gear, an integral spiral and concentric periphery, a brake-chain attached to said drum and adapted to operate from the said spiral and concentric periphery with a variable leverage, and a pinion in mesh with said gear, and actuated by the brake-post, substantially as and for thepurpose set forth.

4. In a brake-actuating device, the combination with a brake-actuating spiral drum and gear, of a recess formed in the periphery at the greatest diameter of said drum to receive the terminal link of the brake-chain, andabolt adapted to pass through said link and fasten it to said spiral drum, substantially as shown and for the purpose set forth.

5. In a brake-actuating device, the combination with roller-bearings, of a brake-actuating spiral drum and gear, a pinion in mesh with said gear and carried on the lower end of the brake-post, and a brake-chain operating with a variable leverage from the spiral and concentric periphery of said drum, substantially as shown and for the purpose set forth.

6. In a brake-operating device, the combination of a brake-actuating spiral drum and gear with means for turning the said gear and a brake-chain operating with variable leverage from the said spiral and cylindrical parts of the drum; the said spiral part diminishing in diameter from the said gear and being of parabolic curve in its largest part, substantially as set forth. I

7. In brake-actuating mechanism, a single piece, consisting of a gear-wheel, a parabolic spiral part, tapering therefrom, and a cylin- IOO IIO

IIS

drica] part at the end of the latter, in oombition, in the presence of tWo Witnesses, this 26th nation With a chain, Winding from the broadday of August, 1903.

est portion of said spiral part, and a pinion, y carried by the brake-post, which meshes With JOHN LANGFORD PEALOQK 5 the said gear-Wheel, to turn the same sub- Witnesses:

stantially as set forth. CHARLES L. LAWRIE,

In testimony whereof I sign this specica- H. DIXON.- 

